Motor direct drive air pump and related applications thereof

ABSTRACT

A motor direct drive air pump comprises a housing, a first shaft, and a second shaft. The housing is formed with a left space and a right space; one of the spaces is a compression chamber having an air inlet and an air outlet; the other space has a transmission chamber and a driving chamber; stators are disposed in the driving chamber. A first shaft is disposed through a central partition of the housing; a first impeller is embedded at a portion of the first shaft located in the compression chamber, while a first gear is embedded at a portion of the first shaft located in the transmission chamber, and rotors are embedded at a portion of the first shaft located in the compression chamber. A second shaft is disposed through the central partition of the housing; a second impeller is embedded at a portion of the second shaft located in the compression chamber, while a second gear is embedded at a portion of the second shaft located in the transmission chamber, and the second impeller and the second gear are respectively coupled to the first impeller and the first gear. Therefore, a power outputted from a motor directly drives the first and the second impellers and allow the air pump to operate, without any additional coupling.

FIELD OF THE INVENTION

The invention relates to an air pump, and more particularly to a motordirect drive air pump having a motor directly outputs power to drive theair pump, and the outputted power does not need to go through anadditional coupling.

DESCRIPTION OF PRIOR ART

A conventional ventilation device usually comprises a housing with anair inlet and an air outlet, and has therein a pair of impellers thatmay be coupled to each other and rotate toward opposite directions,respectively. When one of the impellers passes by the air inlet, a fixedamount of air is captured between the impellers and the housing, thentransported and allowed to exit via the air outlet by the rotatingimpellers. As the rotation of the impellers is repeated, the ventilationdevice may put out a fixed proportion of air.

A spiral pump of prior arts having a driving valve and a piston wasdisclosed in the U.S. Pat. No. 4,772,187. A plurality of arc-shapedsurfaces are externally disposed on the driving valve, while a pluralityof arc-shaped indentations are internally disposed on the main shaft ofthe driving valve, and the piston includes a plurality of semi-ellipsoidblades and a raised portion. When driven by an external force, thepiston of the pump is allowed to spin, so that the liquid within thepump pushes the liquid around the inlet to the outlet under pressure.

A spiral compressor of prior arts having a spiral serrated male rotorand a spiral serrated female rotor that may be coupled together wasdisclosed in the U.S. Pat. No. 6,948,915. The compressor is connected toa housing, and the housing has a high-speed electric motor therein, themotor comprises a rotor, a stator, and an output shaft. The output shaftmay drive at least a male rotor and a female rotor.

The U.S. Pat. No. 6,439,865 also discloses an air pump of prior arts,which comprises a chamber disposed in a housing, and has a suctionportion, a pressurizing portion, and a conversion portion formedtherein. The chamber has therein a pair of rotors that may be coupled toeach other, and each of the rotors has at least three impellers disposedthereon; the impellers of the two rotors are disposed toward differentdirections, and thus defining spaces between the impellers in the airpump.

The underlying mechanism of the aforesaid compressors and air pumps isconsiderably similar to that of the ventilation device, in which a spaceis present and has pairs of impellers that may be coupled to each otherdisposed therein. The impellers or rotors are driven via an externaldriving device (such as a motor), so as to push the air or liquid in thespace from an inlet to an outlet.

However, the ventilation devices of the prior arts must rely on acoupling linked to an external driving device (such as a motor), so asto be driven by a force and operate. This renders the overall size ofthe ventilation device needlessly large, and results in the fact thatthe ventilation device must be built with an excessive number ofmechanical parts, thus the ventilation device not only occupies a lot ofphysical space, but also costs more to manufacture.

SUMMARY OF THE INVENTION

In light of the aforesaid problems, an air pump with smaller physicalsize and less mechanical parts is required, and the invention hasproposed a novel and more advanced motor direct drive air pump inresponse to such requirement. The motor direct drive air pump of theinvention comprises a housing, a first shaft, and a second shaft. Thehousing has a left cover, a right cover, and a central partition to forma left space and a right space, wherein one of the spaces is acompression chamber having at least an air inlet and an air outletopenly disposed on lateral walls thereof; the other space has atransmission chamber and a driving chamber, and stators are disposed inthe driving chamber. Moreover, the first shaft is fittingly disposedthrough the central partition of the housing; a first impeller isembedded at a portion of the first shaft located in the compressionchamber; a first gear is embedded at a portion of the first shaftlocated in the transmission chamber, and a rotor is embedded at aportion of the first shaft located in the driving chamber. Furthermore,the second shaft is fittingly disposed through the central partition ofthe housing; a second impeller is embedded at a portion of the secondshaft located in the compression chamber; a second gear is embedded at aportion of the second shaft located in the transmission chamber, and thesecond impeller and the second gear are respectively coupled to thefirst impeller and the first gear. Therefore, a power outputted from amotor may directly drive the first impeller and the second impeller inthe compression chamber and allow the air pump to operate, withoutneeding to go through an additional coupling.

A primary objective of the invention is to propose a motor direct driveair pump having a smaller physical size.

Another objective of the invention is to propose a motor direct driveair pump having less mechanical parts.

Still another objective of the invention is to propose a motor directdrive air pump having less transmission loss over forces generated froma motor.

Still another objective of the invention is to propose a motor directdrive compressor having a smaller physical size.

Still another objective of the invention is to propose a motor directdrive compressor having less mechanical parts.

Still another objective of the invention is to propose a motor directdrive compressor having less transmission loss over forces generatedfrom a motor.

A further objective of the invention is to propose a motor direct drivevacuum pump having a smaller physical size.

A further objective of the invention is to propose a motor direct drivevacuum pump having less mechanical parts.

A further objective of the invention is to propose a motor direct drivevacuum pump having less transmission loss over forces generated from amotor.

BRIEF DESCRIPTION OF DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objectives can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying diagrams, wherein:

FIG. 1 is a three-dimensional view that shows a motor direct drive airpump according to a first preferred embodiment of the invention.

FIG. 2 is an exploded view that shows a motor direct drive air pumpaccording to a first preferred embodiment of the invention.

FIG. 3 is a sectional view that shows a motor direct drive air pumpaccording to a first preferred embodiment of the invention.

FIGS. 4A to 4K are sketching views that show the allocation of bearingsproposed in the invention.

FIG. 5 is a sectional view that shows a motor direct drive air pumpaccording to a second preferred embodiment of the invention.

FIG. 6 is a sectional view that shows a motor direct drive compressoraccording to a third preferred embodiment of the invention.

FIG. 7 is a sectional view that shows a motor direct drive compressoraccording to a fourth preferred embodiment of the invention.

FIG. 8 is a sectional view that shows a motor direct drive air pumpaccording to a seventh preferred embodiment of the invention.

FIG. 9 is a sectional view that shows a motor direct drive air pumpaccording to a eighth Preferred embodiment of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A motor direct drive air pump is disclosed in the invention, whichutilizes the principle of air transmission in air pumps understood byanyone of ordinary skill in the art, and will not be described infurther details hereafter. Moreover, it should be noted that drawingsmentioned in the following paragraphs are used to illustrate relevantstructures of the invention, and are not necessarily drawn according tothe actual sizes of the disclosed content.

The First Preferred Embodiment

A first preferred embodiment is shown in FIGS. 1, 2, and 3. A motordirect drive air pump 1 comprises a housing 10, a first shaft 11, and asecond shaft 12. The housing 10 has a left cover 101, a right cover 102,and a central partition 103 to form a left space and a right space, andthe right cover 102 may further include an optional cover 1021 to allowfor further combination. One of the spaces is a compression chamber 104having at least an air inlet 1041 and an air outlet 1042 openly disposedon lateral walls thereof; the other space has a transmission chamber 105and a driving chamber 106, and stators 1061 are disposed in the drivingchamber 106.

The first shaft 11 is fittingly disposed through the central partition103 of the housing 10; a first impeller 13 is embedded at a portion ofthe first shaft 11 located in the compression chamber 104; a first gear14 is embedded at a portion of the first shaft 11 located in thetransmission chamber 105, and a rotor 1062 is embedded at a portion ofthe first shaft 11 located in the driving chamber 106. Furthermore, thesecond shaft 12 is fittingly disposed through the central partition 103of the housing 10; a second impeller 15 is embedded at a portion of thesecond shaft 12 located in the compression chamber 104; a second gear 16is embedded at a portion of the second shaft 12 located in thetransmission chamber 105, and the second impeller 15 and the second gear16 are respectively coupled to the first impeller 13 and the first gear14. Therefore, a power outputted from a motor 17 may directly drive thefirst impeller 13 and the second impeller 15 in the compression chamber104 and allow the air pump 1 to operate, without needing to go throughan additional coupling.

In the aforesaid embodiment, the first impeller 13 and the secondimpeller 15 have the same number of blades, while in some otherapplication the first impeller and the second impeller may havedifferent number of blades. In addition, the motor direct drive air pump1 may further comprise a control circuit (not shown) to control theoperation of the motor 17.

Referring to FIG. 3, the central partition 103 may further comprisecylindrical flanges 1031 to the left, to the right, or to bothdirections thereof simultaneously, so that the left cover 101 or theright cover 102 may close over thereon.

FIGS. 4A to 4K show the allocation of bearings proposed in theinvention, wherein a bearing 107 may be disposed in the centralpartition 103, the left cover 101, and the right cover 102, and thelocation of the bearing 107 may be freely arranged according to therequirements that arise from actual operation and mechanical balance ofthe air pump 1. For example, the bearing 107 may be disposed at wherethe first shaft 11 is embedded on the left cover 101, or at where thesecond shaft 12 is embedded on the left cover 101, or at where the firstshaft 11 is embedded on the right cover 102, or at where the secondshaft 12 is embedded on the right cover 102. The bearings 107 may alsobe disposed in pairs at where the first shaft 11 is embedded on the leftcover 101 and on the central partition 103, or at where the second shaft12 is embedded on the left cover 101 and on the central partition 103,or at where the first shaft 11 is embedded on a left side and a rightside of the central partition 103, or at where the first shaft 11 isembedded on the right cover 102 and on the central partition 103, or atwhere the second shaft 12 is embedded on the right cover 102 and on thecentral partition 103.

The Second Preferred Embodiment

A second preferred embodiment is shown in FIG. 5, which is a sectionalview of a motor direct drive air pump. The motor direct drive air pump 1comprises a first housing 18, a second housing 19, a first shaft 11, anda second shaft 12. The first housing 18 has a left cover 101, a rightcover 102, and a central partition 103 to form a left space and a rightspace, wherein one of the spaces is a transmission chamber 105; theother space is a compression chamber 104 with at least an air inlet (notshown) and an air outlet (not shown) openly disposed on lateral wallsthereof. The second housing 19 is disposed outside of the right cover102 for forming a driving chamber 106, and stators 1061 are disposed inthe driving chamber 106.

The first shaft 11 is fittingly disposed into the transmission chamber105, the compression chamber 104, and the driving chamber 106; a firstimpeller 13 is embedded at a portion of the first shaft 11 located inthe compression chamber 104; a first gear 14 is embedded at a portion ofthe first shaft 11 located in the transmission chamber 105, and a rotor1062 is embedded at a portion of the first shaft 11 located in thedriving chamber 106. The second shaft 12 is fittingly disposed throughthe central partition 103; a second impeller 15 is embedded at a portionof the second shaft 12 located in the compression chamber 104; a secondgear 16 is embedded at a portion of the second shaft 12 located in thetransmission chamber 105, and the second impeller 15 and the second gear16 are respectively coupled to the first impeller 13 and the first gear14. Therefore, a power outputted from a motor 17 may directly drive thefirst impeller 13 and the second impeller 15 in the compression chamber104 and allow the air pump 1 to operate, without needing to go throughan additional coupling.

In the aforesaid embodiment, the first impeller 13 and the secondimpeller 15 have the same number of blades, while in some otherapplication the first impeller and the second impeller may havedifferent number of blades. In addition, the motor direct drive air pump1 may further comprise a control circuit (not shown) to control theoperation of the motor 17.

The central partition 103 may further comprise cylindrical flanges 1031to the left, to the right, or to both directions thereof simultaneously,so that the left cover 101 or the right cover 102 may close overthereon.

According to the allocation of a bearing proposed in the invention, abearing 107 may be disposed in the central partition 103, the left cover101, the right cover 102, and the second housing 19, and the location ofthe bearing 107 may be freely arranged according to the requirementsthat arise from actual operation and mechanical balance of the air pump1. For example, the bearing 107 may be disposed at where the first shaft11 is embedded on the left cover 101, or at where the second shaft 12 isembedded on the left cover 101, or at where the first shaft 11 isembedded on the central partition 103, or at where the second shaft 12is embedded on the central partition 103, or at where the first shaft 11is embedded on the right cover 102, or at where the second shaft 12 isembedded on the right cover 102, or at where the first shaft 11 isembedded on the second housing 19, or at where the second shaft 12 isembedded on the second housing 19. Further, the bearing 107 may also bedisposed in pairs to make the air pump 1 more balanced.

The Third preferred Embodiment

A third preferred embodiment is shown in FIG. 6, which is a sectionalview of a motor direct drive compressor having identical characteristicsas the aforesaid first embodiment. However, a compressor requires higherair impermeability than that of an air pump in order to providecompressed air of higher pressure. Therefore, seals 20 such as O-shapedrings are disposed at where the first shaft 11 and the second shaft 12are fittingly disposed through the central partition 103 in thisembodiment, and thinly-formed airtight rings 1011 may also be disposedat where the left cover 101 and the central partition 103 are joined ifrequired. As a result, a power outputted from a motor may directly drivethe first impeller and the second impeller in the compression chamberwithout going through an additional coupling, and allow the compressorto output compressed air from the air outlet.

The Fourth Preferred Embodiment

A fourth preferred embodiment is shown in FIG. 7, which is a sectionalview of a motor direct drive compressor having identical characteristicsas the aforesaid third embodiment. However, a compressor requires higherair impermeability than that of an air pump in order to providecompressed air of higher pressure. Therefore, seals 20 such as O-shapedrings are disposed at where the first shaft 11 and the second shaft 12are fittingly disposed through the central partition 103 in thisembodiment, and thinly-formed airtight rings 1021 may also be disposedat where the right cover 102 and the central partition 103 are joined ifrequired. As a result, a power outputted from a motor may directly drivethe first impeller and the second impeller in the compression chamberwithout going through an additional coupling, and allow the compressorto output compressed air from the air outlet.

The Fifth Preferred Embodiment

The invention further proposes a fifth preferred embodiment, which is amotor direct drive vacuum pump that has identical characteristics as thefirst and the fourth embodiments described above. The air inlet thereofis connected to an exterior pneumatic pipeline, when a power outputtedfrom a motor directly drives the first impeller and the second impellerin the compression chamber, the vacuum pump is allowed to draw air fromthe exterior pneumatic pipeline via the air inlet and output the air viathe air outlet, so as to make the exterior pneumatic pipeline vacuumed.

The Sixth Preferred Embodiment

The invention further proposes a sixth preferred embodiment, which is amotor direct drive vacuum pump that has identical characteristics as thethird and the sixth embodiments described above. The air inlet thereofis connected to an exterior pneumatic pipeline, when a power outputtedfrom a motor directly drives the first impeller and the second impellerin the compression chamber, the vacuum pump is allowed to draw air fromthe exterior pneumatic pipeline via the air inlet and output the air viathe air outlet, so as to make the exterior pneumatic pipeline vacuumed.

The Seventh Preferred Embodiment

A seventh preferred embodiment is shown in FIG. 8, which is a sectionalview of a motor direct drive air pump having identical characteristicsas the aforesaid first embodiment, and further comprises a centralpartition 103 formed from a first partition 108 adjacent to thecompression chamber 104 and a second partition 109 adjacent to thetransmission chamber 105 in the housing 10, and a non-contact open spaceis formed at outside of where the first partition 108 and the secondpartition 109 are joined for facilitating airflow. A pair of seals 20are disposed at where the first shaft 11 and the second shaft 12 arefittingly disposed through the first partition 108, such as O-shapedrings; a pair of bearings 107 are disposed at where the first shaft 11and the second shaft 12 are fittingly disposed through the secondpartition 109. As a result, condensation of water vapor may be preventedand further facilitate the operation of the air pump 1.

In this embodiment, junctions between the first partition 108 and thesecond partition 109 may be located at four opposing corners between thefirst partition 108 and the second partition 109. Spacers 1031 arefurther disposed at the junctions, so that an open space is formedbetween the first partition 108 and the second partition 109. Otherwise,protrusions (not shown) may also be further extended from the junctionsbetween the first partition 108 and the second partition 109, so that anopen space is formed therebetween.

The Eighth Preferred Embodiment

A eighth Preferred embodiment is shown in FIG. 9, which is a sectionalview of a motor direct drive air pump having identical characteristicsas the aforesaid third embodiment, and further comprises a centralpartition 103 formed from a first partition 108 adjacent to thecompression chamber 104 and a second partition 109 adjacent to thetransmission chamber 105 in the housing 10, and a non-contact open spaceis formed at outside of where the first partition 108 and the secondpartition 109 are joined for facilitating airflow. A pair of seals 20are disposed at where the first shaft 11 and the second shaft 12 arefittingly disposed through the first partition 108, such as O-shapedrings; a pair of bearings 107 are disposed at where the first shaft 11and the second shaft 12 are fittingly disposed through the secondpartition 109. As a result, condensation of water vapor may be preventedand further facilitate the operation of the air pump 1.

In this embodiment, junctions between the first partition 108 and thesecond partition 109 may be located at four opposing corners between thefirst partition 108 and the second partition 109. Spacers (as shown inthe seventh preferred embodiment)are further disposed at the junctions,so that an open space is formed between the first partition 108 and thesecond partition 109. Otherwise, protrusions (as shown in the eleventhpreferred embodiment)may also be further extended from the junctionsbetween the first partition 108 and the second partition 109, so that anopen space is formed therebetween.

The Ninth Preferred Embodiment

The invention further proposes a Ninth Preferred embodiment, which is amotor direct drive compressor that has identical characteristics as thetenth embodiments described above. Because a compressor requires higherair impermeability than that of an air pump in order to providecompressed air of higher pressure, a pair of seals 20 such as O-shapedrings may be disposed at where the first shaft 11 and the second shaft12 are fittingly disposed through the first partition 108 in thisembodiment, and thinly-formed airtight rings 1011 may be furtherdisposed at where the left cover 101 and the central partition 103 arejoined if required.

The Tenth Preferred Embodiment

The invention further proposes a Tenth Preferred embodiment, which is amotor direct drive compressor that has identical characteristics as thetwelfth embodiments described above. Because a compressor requireshigher air impermeability than that of an air pump in order to providecompressed air of higher pressure, a pair of seals 20 such as O-shapedrings may be disposed at where the first shaft 11 and the second shaft12 are fittingly disposed through the first partition 108 in thisembodiment, and thinly-formed airtight rings 1011 may be furtherdisposed at where the left cover 101 and the central partition 103 arejoined if required.

The Eleventh Preferred Embodiment

The invention further proposes a Eleventh Preferred embodiment, which isa motor direct drive vacuum pump that has identical characteristics asthe tenth and the thirteenth embodiments described above. The air inletthereof is connected to an exterior pneumatic pipeline, when a poweroutputted from a motor directly drives the first impeller and the secondimpeller in the compression chamber, the vacuum pump is allowed to drawair from the exterior pneumatic pipeline via the air inlet and outputthe air via the air outlet, so as to make the exterior pneumaticpipeline vacuumed.

The Twelfth Preferred Embodiment

The invention further proposes an Twelfth Preferred embodiment, which isa motor direct drive vacuum pump that has identical characteristics asthe twelfth and the fifteenth embodiments described above. The air inletthereof is connected to an exterior pneumatic pipeline, when a poweroutputted from a motor directly drives the first impeller and the secondimpeller in the compression chamber, the vacuum pump is allowed to drawair from the exterior pneumatic pipeline via the air inlet and outputthe air via the air outlet, so as to make the exterior pneumaticpipeline vacuumed.

Although particular embodiments of the invention has been described indetails for purposes of illustration, it will be understood by one ofordinary skill in the art that numerous variations will be possible tothe disclosed embodiments without going outside the scope of theinvention as disclosed in the claims.

1. A motor direct drive air pump, comprising: a housing having a leftcover, a right cover, and a central partition to form a left space and aright space, wherein one of the spaces is a compression chamber havingat least an air inlet and an air outlet openly disposed on lateral wallsthereof; the other space has a transmission chamber and a drivingchamber, and stators are disposed in said driving chamber; a first shaftbeing fittingly disposed through the central partition of the housing; afirst impeller being embedded at a portion of the first shaft located inthe compression chamber; a first gear being embedded at a portion of thefirst shaft located in the transmission chamber, and a rotor beingembedded at a portion of the first shaft located in the driving chamber;and a second shaft being fittingly disposed through the centralpartition of the housing; a second impeller being embedded at a portionof the second shaft located in the compression chamber; a second gearbeing embedded at a portion of the second shaft located in thetransmission chamber, and the second impeller and the second gear arerespectively coupled to the first impeller and the first gear;therefore, a power outputted from a motor may directly drive the firstimpeller and the second impeller in the compression chamber and allowthe air pump to operate, without needing to go through an additionalcoupling.
 2. The motor direct drive air pump according to claim 1,further comprising a plurality of seals, said seals are disposed atwhere the left cover and the central partition are joined, and at wherethe first shaft and the second shaft are fittingly disposed through thecentral partition.
 3. A motor direct drive air pump, comprising: a firsthousing having a left cover, a right cover, and a central partition toform a left space and a right space, wherein one of the spaces is atransmission chamber; the other space is a compression chamber having atleast an air inlet and an air outlet openly disposed on lateral wallsthereof; a second housing being disposed outside of the right cover forforming a driving chamber, and stators are disposed in said drivingchamber; a first shaft being fittingly disposed into the transmissionchamber, the compression chamber, and the driving chamber; a firstimpeller being embedded at a portion of the first shaft located in thecompression chamber; a first gear being embedded at a portion of thefirst shaft located in the transmission chamber, and a rotor beingembedded at a portion of the first shaft located in the driving chamber;and a second shaft being fittingly disposed through the centralpartition of the housing; a second impeller being embedded at a portionof the second shaft located in the compression chamber; a second gearbeing embedded at a portion of the second shaft located in thetransmission chamber, and the second impeller and the second gear arerespectively coupled to the first impeller and the first gear;therefore, a power outputted from a motor may directly drive the firstimpeller and the second impeller in the compression chamber and allowthe air pump to operate, without needing to go through an additionalcoupling.
 4. The motor direct drive air pump according to claim 3,further comprising a plurality of seals, said seals are disposed atwhere the right cover of the first housing and the central partition arejoined, and at where the first shaft and the second shaft are fittinglydisposed through the central partition.
 5. A motor direct drive airpump, comprising: a housing having a left cover, a right cover, and acentral partition to form a left space and a right space, wherein one ofthe spaces is a compression chamber having at least an air inlet and anair outlet openly disposed on lateral walls thereof; the other space hasa transmission chamber and a driving chamber, and stators are disposedin the driving chamber; a first shaft being fittingly disposed throughthe central partition of the housing; a first impeller being embedded ata portion of the first shaft located in the compression chamber; a firstgear being embedded at a portion of the first shaft located in thetransmission chamber, and a rotor being embedded at a portion of thefirst shaft located in the driving chamber; and a second shaft beingfittingly disposed through the central partition of the housing; asecond impeller being embedded at a portion of the second shaft locatedin the compression chamber; a second gear being embedded at a portion ofthe second shaft located in the transmission chamber, and the secondimpeller and the second gear are respectively coupled to the firstimpeller and the first gear; wherein the central partition of thehousing is constructed via joining together a first partition adjacentto the compression chamber and a second partition adjacent to thetransmission chamber, and a non-contact open space is formed at outsideof where the first partition and the second partition are joined forfacilitating airflow; pairs of seals are disposed at where the firstshaft and the second shaft are fittingly disposed through the firstpartition, and pairs of bearings are disposed at where the first shaftand the second shaft are fittingly disposed through the secondpartition; therefore, a power outputted from a motor may directly drivethe first impeller and the second impeller in the compression chamberand allow the air pump to operate, without needing to go through anadditional coupling.
 6. A motor direct drive air pump, comprising: afirst housing having a left cover, a right cover, and a centralpartition to form a left space and a right space, wherein one of thespaces is a transmission chamber; the other space is a compressionchamber having at least an air inlet and an air outlet openly disposedon lateral walls thereof; a second housing being disposed outside of theright cover for forming a driving chamber, and stators are disposed inthe driving chamber; a first shaft being fittingly disposed into thetransmission chamber, the compression chamber, and the driving chamber;a first impeller being embedded at a portion of the first shaft locatedin the compression chamber; a first gear being embedded at a portion ofthe first shaft located in the transmission chamber, and a rotor beingembedded at a portion of the first shaft located in the driving chamber;and a second shaft being fittingly disposed through the centralpartition of the housing; a second impeller being embedded at a portionof the second shaft located in the compression chamber; a second gearbeing embedded at a portion of the second shaft located in thetransmission chamber, and the second impeller and the second gear arerespectively coupled to the first impeller and the first gear; whereinthe central partition of the housing is constructed via joining togethera first partition adjacent to the compression chamber and a secondpartition adjacent to the transmission chamber, and a non-contact openspace is formed at outside of where the first partition and the secondpartition are joined for facilitating airflow; pairs of seals aredisposed at where the first shaft and the second shaft are fittinglydisposed through the first partition, and pairs of bearings are disposedat where the first shaft and the second shaft are fittingly disposedthrough the second partition; therefore, a power outputted from a motormay directly drive the first impeller and the second impeller in thecompression chamber and allow the air pump to operate, without needingto go through an additional coupling.